When taking an image with a camera moving during a period of exposure, an object in the image that is not moving at the same rate as the camera may appear blurred or smeared along the direction of relative motion. This effect is often called motion blur. The longer the exposure time, more the imaged object moves with respect to the camera and the more the picture is blurred. One simple solution to avoid motion blur is fixing the camera position with respect to the objects to be captured in the image. There are also techniques such as image stabilization, vibration reduction, and anti-shake techniques to counteract the motion of a camera to reduce motion blur. However, such techniques only apply when the motion blur is caused by a slight motion of the camera, such as shaking, vibrating, etc. These techniques can not help in situations where the camera motion is significant.
Because motion blur is related to the image exposure time, reducing the exposure time can reduce the amount of motion blur. However, a shorter exposure time also results in a lower amount of light entering the camera sensor, which in turn, affects the quality of the picture. That is, a picture produced with a shorter exposure time appears to be darker than a picture produced with a longer exposure time.
With the introduction of digital cameras and advances of digital imaging, there are also efforts to reduce motion blur using software-based image processing techniques to process digitalized pictures (or digital images) after they are produced. However, because digital images alone do not provide information about the camera movement during exposures, results from software-based techniques are often not as good as solutions applied on the camera itself.